The source he posted on Github calls it 'annotated'[1]. I'm guessing it was just a poor choice of word.
[1] https://github.com/logaan/typed-game-of-life/blob/master/src...
[1] https://github.com/logaan/typed-game-of-life/blob/master/src...
I'm not so proficient a developer that I could write any amount of Haskell code without being acutely aware of its statically typed nature.